1. Field of the Invention
The present invention relates to a light guide module, in particular to a multi-axial light guide module constructed by means of the conjunction of the display unit corresponding to the axial light-emitting plane and the light-guiding unit, in which at least two axial light-emitting planes are formed on the light-emitting portion of the light guide.
2. Description of Related Art
As electronic, information and communication technologies progress, mobile telecom and information consumer devices have become indispensable products for daily lives of modern people, in particular small-sized electronic devices such as mobile phones, Personal Digital Assistants (PDA), wired phones, Audio/Video disc players or other relevant electronic devices for family use etc. The above-mentioned products and related devices are all equipped with keypad and status indication systems for message input, control and operation. Therefore, to assist the use of device in a dim, unclear environment, said electronic devices usually require functions of light display or indication. A common approach is to dispose one or more light-emitting tubes and light-emitting components on the circuit board of the electronic device, in which the light-emitting component can emit light to illuminate the back of the keypad or display panel, so as to clearly show the indicative symbol or notation marked on the key surface. While this technology can solve said problem of indication in a dim, unclear environment, its uneven distribution of light intensity presents another problem, in which the portions close to the light source are much brighter and may cause discomfort to human eyes; whereas, the portions far from the light source may be too dim to be clearly observed.
Hence, light guide may be employed to guide the light generated from light source to a prescribed position, or to transform it to a secondary light source of any specific shape, in order to solve the aforementioned problem of insufficient light source, and facilitate extensive application on keypad backlight system used in various cellular phones or PDA's. At the same time, it may be applied to status indication system installed in numerous electronic products, and communication apparatuses as well.
Referring now to FIG. 1, a diagram of a prior art light-guiding device is shown. The light-guiding device comprises: a light guide 10a, and a lens 20a disposed on one end of the light guide 10a. The light guide 10a is in an arc shape, which has a light-receiving end 11a, a light-emitting end 12a and a connecting end 13a connected between the light-receiving end 11a and the light-emitting end 12a. Herein the connecting end 13a is in a curve arc shape for changing the direction of light guidance. The light guide 10a receives light using the light-receiving end 11a, and received light transfers to the light-emitting end 12a through the connecting end 13a, achieving thereby the effects of light guidance and emission.
However, during the transfer of light in the light guide 10a, as the light guidance refracts to the connecting end 13a, due to the curve arc shape thereof, it may cause too much light loss, and light diffuses out through the surface of the light guide 10a from the connecting end 13a, significantly reducing the ratio of light usage.
Accordingly, to obtain a desired level of light intensity, it has to increase light source consumption in the prior art light-guiding device, causing the reduction of battery life in the electronic devices, and meanwhile, generating more unnecessary heat therein. As a result, it is required to propose a structure design with improved light loss level, in order to increase the ratio of light usage.
Refer to FIGS. 2 to 4, wherein a perspective diagram of a light-guiding device commonly used in a mobile phone 1b, a perspective diagram of a light-guiding device 10b disposed in a mobile phone 1b, and a diagram of the conjunction of light-guiding device 10b, circuit board 20b and light-emitting component 30b are respectively shown. Herein the light-guiding device 10b provides the lighting effect on the mobile phone 1b for charging or standby indication. As illustrated in the Figures, essentially, the light-guiding device 10b has a light guide structure, which is disposed within the mobile phone 1b and placed on a circuit board 20b, with correspondence to the a light-emitting component 30b. The light-guiding device 10b comprises: a body 11b, a receiving end 12b disposed on the bottom of the body 11b, a light-emitting end 13b disposed on the top of the body 11b, and a connecting end 14b disposed between the receiving end 12b and the light-emitting end 13b. The receiving end 12b corresponds to the light-emitting component 30b to receive emitted light, and through the guidance of the connecting end 14b, it allows light to emit at the light-emitting end 13b, providing lighting effect for users.
However, from the design of the light-guiding device 10b, it can be seen that it provides merely one axial light-emitting display. In other words, it can offer light-emitting prompt only through light-emitting effect on one single axial plane (e.g. front side) of the mobile phone 1b. Due to the angle of sight, when the mobile phone 1b is rotated to a certain angle, the surface brightness decreases because of the restriction of reflection angle, thus it can not easily provide effective light-emitting result on other axle (for example, from lateral direction), causing inconvenience for users in the course of observation.
From the above-stated description, it can be appreciated that the prior art light-guiding device, in practical use, has several inconvenience and defects. In view of such inconvenience and defects, it is required to design a light guide structure capable of performing multi-axial light-emitting display, thereby improving the disadvantage of inconvenience due to the angle of sight, which allows light-emitting display only on one axial plane; additionally, reducing the high light loss ration during the course of light guidance in the light guide, further enhancing the efficiency of light emission in light guide.